Technical Field
The present disclosure relates to an analog output module for outputting an analog signal, and more particularly, to an output adjustment device of an analog output module so as to verify a normal operation thereof for use in a programmable logic controller (hereinafter, referred to as a PLC).
Description of the Related Art
In typical industrial sites, automatic facilities have been comprised of mechanical equipment using a relay and the like. For changing functions of the automatic facilities comprised of the mechanical equipment, there may be difficulty in revising wirings of an internal circuit in each of the equipment. To address such a difficulty, a PLC has been made.
A PLC is a programmable logic controller. Generally, the PLC serves as a computer, and receives a signal from a machine and processes the signal according to an internally programmed procedure to output the processed signal back to the machine. The PLC replaces functions of a control instrument such as a relay, a timer, a counter, and the like with a semiconductor device such as an integrated device, a transistor, and the like, and may be program-controlled by adding a numerical calculation function to a basic sequence control function. Additionally, the PLC performs a predetermined logic according to a pre-stored program in an internal memory thereof. The PLC may be applicable to various works such as equipment control, a numeric setting of equipment, a time control, a real time monitoring, a real time data collecting, an operating of safety equipment, and the like.
The PLC is provided with an analog output module for providing a signal to a machine of an automatic facility and the like, and an analog input module for receiving a signal from the machine. The analog input module converts an analog signal provided from a machine into a digital signal to provide an internal arithmetic operation unit with the converted digital signal. The analog output module receives a digital signal reflecting an arithmetic operation result provided from the arithmetic operation unit and converts the received digital signal into an analog signal to transmit the converted analog signal to the machine. At this point, the analog output module converts a digital signal output from a micro processing unit (MPU) into an analog signal to output the converted analog signal to an external load device.
The PLC is a general-purpose controller used in industrial sites and an external load system has a variety of forms. When various load systems are conducted a trial run, a wiring error or a malfunction of a load device may occur such that there is a need to implement a system to be maintainable rapidly.
To output analog voltage and current, a typical analog module for a PLC is directly programmed by a user using a debugging tool such as a programming and debugging tool (PADT). In addition, a method of connecting to a PLC and downloading a program may be used, or high-priced simulation equipment may be installed and used. Even though the high-priced simulation equipment is installed, this equipment is required for each of output channels such that an installation cost may be increased by n times. Moreover, a separate transportation for configuring simulation equipment is required such that there is difficulty in a rapid maintenance.